Mustard gas-destroying paint



United States Patent 2,931,844 MUSTARD GAS-DESTROYING PAINT Harry-Scherr, Baltimore, Md., assignor to the United States of America as represented by the Secretary of War No Drawing. Application June 8, 1944 Serial No. 539,371

7 Claims. (Cl. 260738) (Granted under Title 35, US. Code (1952), see. 266) The invention described herein may be manufactered and used by or for the Government, for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a paint which destroys on contact bis(betachlorethyl) sulfide, commonly known as mustard gas.

Mustard gas which contaminates surfaces of military or naval equipment, such as tanks, trucks, gun mounts, airfield runways and hangars, boat decks and other surfaces, constitutes a hazardto personnel for long periods of time. Such contamination may occur from airplane spraying of mustard gas; or from bursting shells or bombs. Mustard gas is extremely persistent and objects or surfaces contaminated with this compound are dangerous to personnel even after several weeks exposure to the weather.

It is known that active chlorine will react with and destroy mustard gas. However, the chlorine must remain active and available over long periods of time, since otherwise the paint will not give the protection desired.

It is the object of this invention to provide a paint which, when applied to a surface, destroys mustard gas penetrating into the paint film; which is non-toxic and noncorrosive; which consists of substances which are compatible with each other; that is, the mustard gas-destroying active ingredient is compatible with the remaining paint ingredients; and which may be applied to ship decks and other exposed surfaces which are liable to be exposed to mustard gas. Included within the scope of surfaces which (g) It should preferably comprise only ingredients readily available in commercial quantities in the United States.

(h) It should be stable in storage; that is, the ingredients of the paint should be compatible.

Although the invention is not limited thereto, it is believed that a mustard-destroying paint would prove of particular value where confined surfaces were exposed to the attack of mustard gas vapor and in situations where small amounts of liquid mustard gas were encountered.

Experiments have been made over a period of time with many substances as possible ingredients for a mustard gas-destroying paint. The ideal material for this purpose would be an ingredient which could be mixed with a standard paint, but which would render the coating capable of neutralizing a contamination of mustard gas of a degree such as might be expected in service. This ideal has been ditficult of attainment because most materials which would destroy mustard gas would react with the vehicle in the paint. The quantity which it would be necessary to add to the standard paint, to obtain the necessary neutralizing power, would also assume impossible proportions. A search has been made for mustard gas-destroying ingredients which, among other desired qualities, will be efliective in small proportions by weight in the paint.

The base finally selected for the mustard gas-destroying paints according to this invention is a highly chlorinated rubber. This substance is readily soluble in the common solvents. Paints made from it are easy to apply and yield excellent films. The great difiiculty in formulating mustard gas-destroying paints is that the active agent (chlorine) has a tendency to react chemically with a wide variety of materials, especially the materials ordinarily used in compounding paints. As a result of this reaction the active agent decreases in activity, and hence in its ability to neutralize mustard gas. However, if organic ingredients are already chlorinated, the reaction between them and the active agent is greatly reduced. In the following table are given formulas of mustard gas-destroying paints which have been found suitable, although the invention is not intended to be limited thereto.

TABLE Formulas of HS-Destroying Paints Formula No 136C 136D 139 139A 142 152A 154A 213A 214 215 216 Components: Percent Percent Percent Percent Percent Percent Percent Percent Percent Percent Percent A highly chlorinated rubber... 19. 7 21. 2 21. 2 19. 6 23.5 21. 2 21. 2 19. 0 17. 8 16.7 17. 9 Chlorinated paralfin 3. 2 3. 5 3. 5 3. 2 3. 8 3. 5 3. 5 2.0 1. 8 1. 7 1. 8 Tumor 3.6 3.8 3.8 3.6 4.3 3.8 3.8 Zinc Oxide. 3. 5 6.7 6. 1 10.0 Ultramarine blue 0.3 0.3 0.3 0.3 0.3 0.3 0. 3 0.2 0.3 0.4 0.5 Lampblaek 0. l 0. 1 0. 1 0. 1 0. 1 0. 1 0. 1 0. 1 0. 1 0. l. Sym dlchlor-bls (2,4,6 trlchlorphenyl)urea.. 9.6 8.9 9.6 8.3 8.9 8.3 Dlchlorodlmethylhydantolnu 8. 9 9. 6 9. 6 5. 3 Tetrachlorethylene 28. 6 23. 0 23. 0 21. 4 25. 5 23. 0 23. 0 40. 0 32. 2 66. 7 32. 2 Monochlorbenzene 35. 6 38. 5 38. 5 42. 9 42. 5 38. 5 38. 5 27. 0 32. 2 32. 2

may be protected are the above-mentioned surfaces, cloth- Paint number 142 18 a highly chlorinated rubber-base paint containing neither sym dichlor-bis (2,4,6 trichlorphenyl) urea nor dichlorodimethylhydantoin.

The difference between No. 136D and No. 152A is in the order in which the ingredients are mixed. In the first, the materials were all ground together; in the latter, the chlorinated parafiin and the highly chlorinated rubber were first dissolved in the solvent and then the solids were ground in. There was no noticeable difference in the final products. Paint numbers 139 and 154A were likewise similar except for the method of preparation.

Tests were made to determine the stability on storage of these paints by measuring the loss in active chlorine upon storage. These tests demonstrated that the paints showed no serious loss in active chlorine up to about two and one-half months. Even this loss in activity may be avoided by keeping the active agent and vehicle separate until needed for use. Nor did paint films exposed to sunlight for eight days suffer any serious loss of active chlorine.

A modification of the paints given in the table above involves the use of a chlorinated diphenyl with the highly chlorinated rubber and the symdichlor-bis(2,4,6-trichlorphenyl)urea. The highly chlorinated rubber is the film-forming base of this paint. It is stable with sym dichlor-bis(2,4,6-trichlorphenyl)urea and is soluble in mustard gas, so that the latter can readily penetrate the film and react with the active agent. In addition, the highly chlorinated rubber produces excellent films having desirable characteristics of hardness and durability. Since these highly chlorinated rubber films are brittle, they need to be plasticized. In the presence of the active agent to sym dichlor-bis (2,4,6 trichlorphenyl) urea, ordinary plasticizers are not suitable, and here a chlorinated diphenyl is substituted for the ordinary plasticizers. The coating laid down from this paint is non-flammable. In fact, the entire paint itself is non-flammable, since non-flammable chlorinated hydrocarbons are the solvents used in the paint.

Although a highly chlorinated rubber has been specified herein, the invention is not limited thereto, as chlorinated rubber of any degree of chlorination is contemplated to fall within the scope of the invention. Also included within the scope of the invention are the various synthetic rubbers, known commercially as neoprene, butyl, buna and others. In the attached claims, it will be understood that the word rubber includes synthetic and natural rubbers.

The composition Titanox employed in preparing paints number 136C, 136D, 139, 139A, 142, 152A and 154A is a well known trade name for titanium dioxide and is employed as a pigment in paints.

The subject matter of this application has previously been disclosed in a copending application, Serial No. 380,796, filed Feb. 27, 1941, now abandoned.

The invention herein described is not limited to the precise details herein disclosed, since variations therein may be made by those skilled in the art without exceeding the scope of the appended claims.

I claim:

1. A mustard gas-destroying paint comprising approximately:

4 2. A mustard gas-destroying paint comprising approximately:

Percent A highly chlorinated rubber 17.8 Chlorinated paraflin 1.8 Zinc oxide 6.7 Ultramarine blue 0.3 Lampblack 0.1 Sym dichlor-bis (2,4,6 trichlorphenyl) urea 8.9 Tetrachlorethylene 32.2 Monochlorbenzene 32.2

3. A mustard gas-destroying paint comprising approximately:

Percent A highly chlorinated rubber 21.2 Chlorinated paratfin 3.5 Titanox 3.8 Ultramarine blue 0.3 Lampblack 0.1 Dichlorodimethylhydantoin 9.6 Tetrachlorethylene 23. Monochlorbenzene 38.5

4. A mustard gas-destroying paint comprising approximately:

Percent A highly chlorinated rubber 17.9 Chlorinated paraflin 1.8 Zinc oxide 10.0 Ultramarine blue 0.5 Lampblack 0.1 Dichlorodimethylhydantoin 5.3 Tetrachlorethylene 32.2 Monochlorbenzene 32.2

5. A mustard gas-destroying paint comprising in the range of about 17 to about 21% of highly chlorinated rubber as a film-forming base and in the range of about 5% to about 10% of an active mustard gas-destroying agent of the group consisting of dichlor-bis (2,4,6-trichlorphenyl) urea and dichlorodimethylhydantoin.

References Cited in the file of this patent UNITED STATES PATENTS 2,114,251 Koch Apr. 12, 1938 2,302,583 Shutt Nov. 17, 1942 FOREIGN PATENTS 486,162 Great Britain May 31, 1938 

1. A MUSTARD GAS-DESTROYING PAINT COMPRISING APPROXIMATELY: PERCENT A HIGHLY CHLORINATED RUBBER -------------------- 21.2 CHLORINATED PARAFFIN --------------------------- 3.5 TITANOX ---------------------------------------- 3.8 ULTRAMARINE BLUE ------------------------------- 0.3 LAMPBLACK -------------------------------------- 0.1 SYM DICHLOR-BIS (2,4,6 TRICHLORPHENYL) UREA ---- 9.6 TETRACHLORETHYLENE ----------------------------- 23.0 MONOCHLORBENZENE ------------------------------- 38.5 